Thousands of birds have died after avian influenza strikes turkey farm in southern Ontario

Canadian officials placed eight farms in southern Ontario under quarantine Tuesday, after an avian influenza outbreak caused the sudden deaths of thousands of birds over several days.

The Canadian Food Inspection Agency said its investigation would look at whether the H5 avian influenza originated from the U.S., where 10 states have suffered an outbreak of highly pathogenic avian influenza. Testing on the strain that struck a turkey farm in southern Ontario is under way, with results expected as soon as later Tuesday.